There are well-known cutting tools such as indexable inserts, drills, miniature drills, and solid type end mills. Indexable inserts are attached to an end of a cutting tool such that the inserts can be freely attached or removed and are used for turning, milling of work materials such as various types of steel and cast ion. Drills and miniature drills are used for drilling of the above-described work materials. Solid type end mills are used for face milling, slotting, and side milling of the above-described work materials. Insert type end mills are removably attached with the indexable inserts and are employed for a cutting operation the same as the solid type end mills.
As a surface-coated cutting tool, there is a well-known surface-coated cutting tool comprising a cutting tool body and a hard coating layer physically vapor-deposited on the surface of the substrate, wherein the substrate is constituted of tungsten carbide (hereafter referred to as WC)-based hardmetal or titanium carbonitride (hereafter referred to as TiCN)-based cermet, and the hard coating layer is a wear-resistant hard layer having an average thickness of 0.8 to 5 μm and comprising a layer of composite nitride containing Ti and Al (hereafter referred to as (Ti,Al)N). Since the (Ti,Al)N is provided with excellent high-temperature hardness, excellent heat resistance by the Al component, and is provided with excellent high-temperature strength by the Ti component, the above-described surface-coated cutting tool is known to exert an excellent cutting performance in a case of continuous cutting or intermittent cutting of various steels and cast irons.
Further, it is also known that the above-described surface-coated cutting tool can be produced using an arc ion plating apparatus which is a type of physical vapor-deposition apparatus schematically shown in FIG. 3. After placing the above-described cutting tool body in the apparatus, the wear-resistant hard coating layer comprising the (Ti, Al)N layer may be deposited as the hard coating layer on the surface of the cutting tool body under conditions comprising: heating the inside of the apparatus at 500° C.; in that state, by a condition of e.g., electric current: 90 A, generating arc discharge between an anode and a Ti—Al containing alloy of a predetermined composition placed as a cathode (evaporation source); simultaneously, as a reaction gas, introducing nitrogen gas into the apparatus to obtain a reaction atmosphere of e.g., 2 Pa; and applying a bias voltage of e.g., −100V to the above-described cutting tool body (For example, Japanese Unexamined Patent Application First Publication, No. H8-209333; Japanese Unexamined Patent Application First Publication, No. H7-310174; Japanese Unexamined Patent Application First Publication, No. H4-26756).